THE bodies of a husband and wife killed in a plane crash off the Waikato coast may never be found, the head of a Navy team searching for the wreckage has admitted.

Eric Hertz, head of the 2degrees cellphone company and his wife Kathy were killed while flying to see their daughter in Timaru on Saturday.

Before ditching into the sea Mr Hertz reported engine trouble.

Warrent Officer James Harper – officer in charge of the Navy’s Mine Countermeasures team – said it was possible their bodies may never be found, but he was taking confidence from the progress of a five-hour, 1km-square sonar scan of the ocean floor this afternoon.

“Everything is based on the best information you get at the time,” APNZ reported Warrant Officer Harper as saying.

Around 20 members of the Navy, police and Coastguard were working hard to retrieve the bodies, which are thought to be with the wreckage 60 metres below the surface.

Sea conditions were fair today, with swells of around 2m.

“Can I put a confidence factor on it? Not necessarily now, but I have a reasonable confidence level in what we’re achieving today.”

If unable to locate the wreckage today, the search area would be widened, but even if it was found, it was not certain divers would be able to reach it.

“Police are thus relying heavily on the expertise of the Navy and their experience in this field,” Sergeant Warren Shaw said.

“One of the major challenges we’re facing is that we’re dealing with an aircraft that has potentially impacted with the water at high speed and broken up.

“To compound things further, there’s the potential for objects from the wreckage to drift up to 5km a day due to … currents.”

Debris from the plane and an oil slick were found about 20km northwest of Kawhia Harbour.